1. Field of the Invention
The present invention relates to a communication method of a wireless terminal communicating to a desired wireless terminal. Both wireless terminals are situated under the same wireless communication environment.
2. Description of the Related Arts
Rapidly increasing uses of the cellular communication networks for the purposes of various data communication have been brought about from a recent advancement in their variety of types. Uses of these cellular communication networks continue to accelerate owing to the introduction of such services as cellular phone service that can have the internet connection and communication service that makes the high-speed delivery of the data possible. In addition to the ever increasing uses of these services which are provided by the operators, even the contents of these services are becoming diverse. A service which supplies the position information of a wireless terminal to a user of the network side and passes it onto another wireless terminal is one example of the diversified services. The example of such services are the service of supplying a timetable of the nearby train station to a wireless terminal based on its position information: and a service of locating the positions of the employees. Japanese unexamined patent publication HEI 10-221106 discloses a technique of informing the network user the position information of the wireless terminals using the internet. This technique is commonly being adopted for a purpose of controlling the positions of the wireless terminals.
As mentioned briefly, various types of the cellular communication networks provided and controlled by the operators are used by various wireless terminals for the purposes of various kinds of data communication. These data communication are the wireless communication from a wireless terminal to a cellular communication network, and vice versa, in other words, the wireless communication involving the operator. In the wireless communication involving the operator, it is the network who supplies the wireless communication mechanisms to the wireless terminal. Not only the wireless communication involving the operator supplying the wireless communication mechanism to the wireless terminal, but also other kinds of wireless communication which is the wireless communication not involving the operator, are becoming widespread. The wireless communication not involving the operator is the wireless communication from a wireless terminal to another wireless terminal. In this case, the wireless communication mechanisms are integrated to the wireless terminal. As an example, the communication method known as infrared data access (IrDA) interface exchanges data between one wireless terminal and another wireless terminal. The infrared data access integrates the wireless communication mechanisms to the wireless terminals. The communication method known as Bluetooth utilizes a high-speed and weak micro wave. The Bluetooth is a communication method from a wireless terminal to a well-known destination wireless terminal. The communication method known as wireless local area network is disclosed in Japanese unexamined patent publication HEI 11-163875. The wireless local area network (wireless LAN) implements the ad hoc network integrating media access control (MAC) to the wireless communication media. This publication discloses the wireless local area network system which deploys a mechanism to register position of a wireless terminal, to give a specific example, this technology is adopted in such locality as art museum, supplying an information to a user holding a wireless terminal, and the system supplies the information on any piece of artwork responding to position of the user holding the wireless terminal in the art museum.
Accordingly, various wireless communication mechanisms are beginning to be integrated to the wireless terminals making them possible to communicate from one wireless terminal to another wireless terminal without involving the operator in its way. Yet still, the mechanisms supplied by the operators allow the users to connect to the network to receive many different kind of services, however, the disadvantages in using their mechanisms are that the users are charged for using these services and also charged for the connection fee. With the increasing number of users using these services, without doubt this will cause a significant amount of communication traffics such that the operators also need more money to reinvest in the new equipment. Not to mention the fact that the wireless communication involving the operator is generally slow in speed. Thus, without doubt that the communication from one wireless terminal to another wireless terminal bypassing the operators such as in public switched telephone network is not at all practical.
On the other hand, the wireless communication not involving the operator is used in a fixed communication from one wireless terminal to another well-known destination wireless terminal using a weak radio wave in a narrow region. This can generally attain the high-speed communication rate. According to one of the aims of the present invention, not only it attempts to solve the pre-mentioned problems, but the present invention also aims to supply the data communication method between the wireless terminals integrating the data communication mechanisms by forming what is essentially a contingent and local network (ad hoc network). In precise terms, the present invention attempts to carry out a service to the wireless terminal by adopting a part of the existing network, setting up a terminal location database having various types of information, and further forming the ad hoc network consisting of wireless terminals, joining any wireless terminals to the ad hoc network formed, and allowing free communication between the joined wireless terminals. This way, even if the communication device in use such as wireless terminal which does not wish to involve the operator, the wireless terminal user can still search and inquire for a service or data provided by the operator, and in response to the inquiry of this wireless terminal, any other wireless terminal user who happens to have the service or the data being requested can send them instead. The application for which its use is limited to a business card exchanges between the wireless terminals is adopted and extended to the extent of exchanging of non-specified amount of services and data. This enables the wireless terminal to utilize the high-speed wireless communication to the unknown wireless terminal at a reasonable cost.